Battery Hybrid System Research Articles

Experimental Test Results of Nine Scheduling Operational Modes of PV and Battery Hybrid System for the Development of Automatic Control Algorithm for Continual Operation without being shut-downed

Experimental Test Results of Nine Scheduling Operational Modes of PV and Battery Hybrid System for the Development of Automatic Control Algorithm for Continual Operation without being shut-downed

Dynamic vulnerability in standalone hybrid renewable energy system

Ensuring continuous power supply in the hybrid renewable energy and battery system is important because power utilization is fundamental to economy and human well-being. Earlier studies have been concerned with the ability to supply a desired amount of power in a long-term static condition in the context of system reliability. Meanwhile, short-term dynamic behavior and its relevant vulnerability in a hybrid system associated with a continuous power supply has been given less attention due to the modeling complexity of the problem. This study uses a parametric approach to assess the dynamic transition of vulnerabilities potentially leading to disruptions in electricity supply throughout a given day to identify a specific vulnerable time. The methodology of quantifying the dynamic vulnerability of power source components during a given day in a hybrid system is developed. Then, the temporal dynamic vulnerability and overall vulnerability in the system are presented by changing the capacity size in the case of a fictitious standalone house. Through the analysis, the approach developed in this study would potentially highlight the greater contribution of the battery to continuous power supply, compared with the solar PV in the hybrid system.

A Multi-Stage Approach to a Hybrid Lead Acid Battery and Supercapacitor System for Transport Vehicles

Lead Acid Batteries (LABs) are used for starting, lighting, and igniting, as well as in air conditioning systems and to supply power to electric engines in transport vehicles (TVs). However, the application of LABs for TVs has faced a number of market challenges, mounted by the upcoming high energy density and long lifespan batteries, such as lithium ion. LABs, on the other hand, are inexpensive. The key research question is, how can the lifespan of LABs used in automotive industries be increased, while still ensuring a low cost solution? Thus, integrating LABs with the supercapacitor (known as an electric double layer capacitor—EDLC) is likely to outperform the competing alternative batteries for TVs. This paper proposes a multiple stage approach to hybrid lead acid batteries and a supercapacitor system for TVs that is capable of maintaining the battery state-of-charge (SOC) at statistically high limits, ranging between 90% and 95%. This SOC target will likely ensure that the lifespan of the hybrid battery system can be elongated (extended) more than its competitors. In this study, the multiple stage approach of concatenated converters has been designed in order to satisfy all energy storage requirements for different characteristics of LABs and the supercapacitor. The designed hybrid system has been simulated using Matrix Laboratory (MATLAB/Simulink (version R2016a, MathWorks, Natick, MA, USA)). The simulated results show that high transient currents from the direct current (DC) bus of LABs, caused by the regenerative braking or deceleration of the TVs, reduce the battery lifespan and induce mechanical stress. The supercapacitor reduces the stress on the LAB by absorbing high transient currents. This, in turn, keeps the LABs’ SOC between 90% and 96% and the voltage at 12 V. As indicated by the simulated results, the hybrid battery SOC is maintained at 90–96% and the terminal voltage is approximately 12 V.

Primary frequency control provided by hybrid battery storage and power-to-heat system

Given the current influx of intermittent renewable energy sources due to the German Energiewende, additional flexibility is needed to guarantee a reliable power supply by varying electricity generation. Battery energy storage systems are playing an important role for the grid stabilization in Germany. This paper analyses the hybrid concept of combining batteries with power-to-heat technology in the environment of primary control reserve. A comparative economic assessment of hybrid and stand-alone battery systems is discussed by making use of a simulation model in MATLAB®. The economic feasibility of a sustainable business model was investigated in accordance with the German regulatory framework. By comparing to a stand-alone battery system providing primary control reserve, simulation results revealed that the combination with a power-to-heat system is another option for providing a reliable frequency regulation. Despite the additional cost of power-to-heat units, grid fees, taxes and expected shorter lifetime of the battery cells, the hybrid solution leads to an improved profitability scenario for investors when compared with a stand-alone battery in a PCR market.

Hybrid renewable energy supply for rural healthcare facilities: An approach to quality healthcare delivery

The lack of modern electricity supply has been a major impediment to proper functioning of the healthcare centers in the rural areas, contributing to high maternal and child mortality rates in a country. Therefore, this study focuses on how to address the identified problem so that the healthcare centers or clinics in the remote areas can provide timely delivery of medical services for the concerned people. This paper, then, presents the analysis of stand-alone hybrid renewable energy systems for basic healthcare services in the rural areas, where there is no grid energy supply or the supply from the existing grid is erratic and unreliable. One major factor that informs the selection of the hybrid energy system in this study is that it promises high reliability compared to a single energy system. The research presents a statistical analysis of the potential of wind and solar energies for a selected rural locations in Nigeria based on the available long-term hourly and daily meteorological data. It employs an optimal technical and economic design and sizing of hybrid electrical power systems’ components such as the wind, PV, battery and inverter systems, using the hybrid optimisation software (HOMER). Results show that Sokoto and Jos sites exist in the high wind potential regions, while the remaining sites are only suitable for small wind applications. Values obtained for global radiation show that all the sites enjoy considerable solar energy potential suitable for varying degree of solar energy applications. PV/wind/diesel/battery hybrid system configuration is considered optimum for rural health center at Iseyin, Sokoto, Maiduguri, Jos and Enugu, while hybrid systems involving PV/diesel/battery is considered ideal for Port-Harcourt, due to the quality of renewable energy potential. Hence, it was concluded that, the abundance of wind and solar resources in the country create an ideal environment for inclusion of renewable energy systems in the design and implementation of standalone power supply systems to improve rural healthcare delivery.

Modeling, realization and test on field of a fuel cell ‐ Na/NiCl2 battery hybrid system as a base transceiver station power supply

Modeling, realization and test on field of a fuel cell ‐ Na/NiCl2 battery hybrid system as a base transceiver station power supply

Optimal sizing of hybrid PV and wind energy system with backup of redox flow battery to postpone grid expansion investments

In this study, economical options to meet the load demand of Hormoz Island as a green Island in future years, located in Iran, are investigated. For this purpose, construction of a new undersea transmission line (UTL) and design of a grid-connected hybrid renewable energy system (RES) are selected as two possible options. Therefore, the optimization problem is modeled as a minimization of cost function including the investment, replacement, operation, and maintenance costs of components, carbon tax, and cost of purchased power from the upstream network as well as the cost of loss of load. It is notable that the grid-connected hybrid RES consists of photovoltaic (PV) and wind energy systems with consideration of redox flow battery storage. The optimization problem is simulated for a 20 year planning horizon subject to technical and geographical constraints of RES. To simulate the problem, the annual hour-based data of wind, solar radiation, and load demand of Hormoz Island are used. Also, wind energy potential of the region is used for the selection of the best turbine for this island. Moreover, an imperialist competitive algorithm and an improved particle swarm optimization algorithm are applied to find the best size and design of the hybrid RES and also the best time to use the RES and the new UTL. Three different scenarios for optimum hybrid RES designing are determined to consider the effects of using the hybrid system to postpone the grid expansion investments. Two of these scenarios have 20 year planning horizon, and one of them optimizes the system for a special year with a specific predicted load demand. The obtained results revealed that the wind/PV/vanadium redox flow battery hybrid system is the best configuration, where the new UTL will be constructed in 2020 with zero load energy shortage.

Hybrid PV-Wind, Micro-Grid Development Using Quasi-Z-Source Inverter Modeling and Control—Experimental Investigation

This research work deals with the modeling and control of a hybrid photovoltaic (PV)-Wind micro-grid using Quasi Z-source inverter (QZsi). This inverter has major benefits as it provides better buck/boost characteristics, can regulate the phase angle output, has less harmonic contents, does not require the filter and has high power performance characteristics over the conventional inverter. A single ended primary inductance converter (SEPIC) module used as DC-DC switched power apparatus is employed for maximum power point tracking (MPPT) functions which provide high voltage gain throughout the process. Moreover, a modified power ratio variable step (MPRVS) based perturb & observe (P&O) method has been proposed, as part of the PV MPPT action, which forces the operating point close to the maximum power point (MPP). The proposed controller effectively correlates with the hybrid PV, Wind and battery system and provides integration of distributed generation (DG) with loads under varying operating conditions. The proposed standalone micro grid system is applicable specifically in rural places. The dSPACE real-time hardware platform has been employed to test the proposed micro grid system under varying wind speed, solar irradiation, load cutting and removing conditions etc. The experimental results based on a real-time digital platform, under dynamic conditions, justify the performance of a hybrid PV-Wind micro-grid with Quasi Z-Source inverter topology.

수소 재순환 특성을 고려한 연료전지 시뮬레이터

In order to compensate a loss from the dynamic, a hydrogen fuel cell supplies the hydrogen more than 10% to its rated capacity. It brings the issue that a utilization rate of fuel cell degrades to 10%, therefore, the method is applied which recirculating the emitted hydrogen after their reaction. When their hydrogen recirculating, it results in emitting not the pure hydrogen but impurity, as a result it enables the electric energy to unstable. When a load requires certain power, a membrane of fuel cell has damaged due to voltage drop. In order to develop the charger which charging the energy into battery in fuel cell and battery hybrid system, it requires protection operation according to fuel cell output characteristic results from hydrogen recirculation. In fuel cell charger, selecting the level of protection operation voltage and current through experiment brings significant problem that damage of costly fuel cell. In this paper, we explain the design and control method of the fuel cell simulator which has output characteristic according to current density, temperature of fuel cell including hydrogen recirculation function and verify the validity through simulation and experiment.

Towards a Solar-Cell Battery Hybrid System

Energy from renewable sources is considered today the only long-term viable solution to the current energy crisis. Appropriate storage solutions, such as batteries, are, however, always required in such systems since energy from renewable sources such as wind solar or tidal has an intermittent character. The efficiency of solar cells, irrespective of the type, has steadily and significantly been improved in the past decade. Today, they are championed as one of the most relevant renewable energy conversion devices in both academic and political media. In a complete solar energy system, solar cells convert solar radiation into electric energy, the excess being stored in lead-acid or Li-ion batteries. So far, solar cells and the batteries were implemented as separated devices. Here, we explored possibilities to develop one single hybrid device, i.e., by integrating the conversion function of the solar cell with the storage function of a battery. We used an organic solar cell and combined it with a lithium-ion battery. Some critical aspects have to be considered beforehand. First, the materials used in the solar cell and the battery have to be chemically compatible since they will be eventually sharing the same case. Second, it is important to find two electrode materials with a potential difference that matches the solar cell voltage (approximately 1.5 V). In addition, the goal for the solar cell is to reach high efficiencies and reasonable open circuit potentials. The organic homo-tandem1 solar cell was built in inverted device architecture. PTB7-Th (Poly([2,6′-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene]{3-fluoro-2[(2-ethyl­hexyl)­carbonyl]thieno[3,4-b]thiophenediyl})) was used as donor and O-IDTBR ((5Z, 5'Z)-5,5'-((7,7'-(4,4,9,9-Tetraoctyl-4,9-dihydro-s-indaceno[1,2-b: 5,6(Benzo[c][1,2,5]thia­dia­zol-7,4-diyl) bis (methanolyliden)) bis (3-ethyl-2-thioxothiazolidin-4 -ein)) as non-fulle­rene acceptor. The intermediate layer was MoO3/Al/PFN-Br. The battery was assembled with carbon-coated lithium vanadium phosphate2 (LVP-C, cathode), LP30 (1M lithium hexa­fluoro­phosphate (LiPF6) in ethylene carbonate (EC) and dimethyl carbonate (DMC); EC:DMC=1:1 (v/v)) and vanadium disulphide3 (VS2, anode) in a Swagelok cell. Full cell measurements of the Cu|VS2|LP30|LVP-C|Al battery in a Swagelok cell showed a constant capacity of 74 mAh/g over 50 cycles. The tandem solar cells reached an open circuit potential (V OC) of 1.9 V and a conversion efficiency slightly above 6 %. The first combined measurements were carried out with the solar cell encapsulated in epoxy resin and connected to the battery. The battery cycled between 0.4 and 1.4 V and was charged with a current density between 25 – 35 mA/cm2 from the solar cell during illumination. To assemble the hybrid device, the Al-supported LVP-C cathode was directly placed on the Ag contact layer of the solar cell (the positive electrode) followed by the separator and the negative electrode of the battery. The battery was activated by soaking it with electrolyte. Finally, the whole solar-cell battery stack was encapsulated with ultraviolet-curable epoxy resin. First measure­ments lead to a successful proof of principle − the integrated battery was successfully charged by the solar cell. These very first results are encouraging and prove the validity of this relatively simple but potentially powerful concept. Further work is scheduled to refine the concept and improve the performances of the hybrid solar cell - battery device. Acknowledgement The work was financed within the project SOLABAT funded by the Klima- und Energiefonds of FFG (Österreichische Forschungsförderungsgesellschaft. Moreover, we thank the Austrian Federal Ministry for Science, Research and Economy as well as the Christian-Doppler Forschungsgesellschaft for the financial support. References Kaltenhauser, V., Rath, T., Edler, M., Reichmann, A. & Trimmel, G. Exploring polymer/nanoparticle hybrid solar cells in tandem architecture. RSC Adv. 3, 18643 (2013).Huang, C., Chen, D., Huang, Y. & Guo, Y. Electrochimica Acta Sol – gel synthesis of Li3V2(PO4)3/C cathode materials with high electrical conductivity. Electrochim. Acta 100, 1–9 (2013).Rout, C. S. et al. Synthesis and characterization of patronite form of vanadium sulfide on graphitic layer. J. Am. Chem. Soc. 135, 8720–8725 (2013).

Dimensioning and Optimization of Hybrid Li-Ion Battery Systems for EVs

Commercial electric vehicles nowadays are powered by a battery system containing one kind of lithium-ion battery cell. Due to the fixed ratio of the cells’ maximum power to nominal energy, the possibilities for designing power and energy of the battery pack independently are limited. The battery system’s energy and maximum power can only be scaled by adapting the number of cells and modules, and the parameters furthermore depend on the characteristics of the cells used. Additional power electronics in the form of one or more dc/dc converters can be used to form a hybrid battery system comprised of more than one pack and different cell technologies. This allows for individually designing each battery pack and thus optimizing the overall battery system specification. This work presents a battery dimensioning and optimization approach for single pack and hybrid battery systems. It is based on an evolutionary optimization algorithm and a detailed, modular Matlab-Simulink vehicle model. Studies on the advantages of hybrid batteries for different vehicle classes were carried out. Results indicate that optimized hybrid battery systems can lead to weight and volume savings and further advantages in total cost of ownership, for example, by enhanced battery life time or reduced investment costs. On the other hand, they require more complex control logic, which is also discussed in this paper.

Assessing the potential of a hybrid battery system to reduce battery aging in an electric vehicle by studying the cycle life of a graphite∣NCA high energy and a LTO∣metal oxide high power battery cell considering realistic test profiles

The utilization of a hybrid battery system (combination of different battery packs via dc/dc converter) in an electric vehicle application is discussed. It is investigated whether battery aging in an electric vehicle can be reduced by using a hybrid battery system. Cycle aging measurements of lithium-ion battery cells were performed at 23 °C against the background of the latter application. Recommendations for hybrid battery system electric vehicle operation are given. For Panasonic NCR 18650 BD cylindrical high energy cells (graphite anode, Li(NiCoAl) O2 cathode), three cycle aging campaigns were conducted systematically, evaluating the impact of charging as well as discharging loads with different time scales and microcycling per driving distance. A significant impact of recuperation pulse duration on aging per driving distance could be observed, whereas varied discharge load characteristics did not vary the aging characteristics. On the basis of differential open circuit voltage analysis, possible degradation mechanisms are discussed. The main driver of capacity loss and resistance increase in cycle aging campaigns with real world driving cycles appears to be the loss of cyclable lithium. Within the operating conditions investigated here, anode aging is intensified with increasing recuperation pulse duration. Another cycle aging campaign with symmetric current rate of 10C for a prismatic high power battery cell (Li4Ti5O12 anode, metal oxide cathode) yielded excellent cycle performance of this cell.

Assessing the potential of an electric vehicle hybrid battery system comprising solid-state lithium metal polymer high energy and lithium-ion high power batteries

In this work the characterization and application of a prototype solid-state lithium metal battery for an electric vehicle application is addressed. This mid-temperature battery is operated at a temperature of 80 °C. In an innovative approach, this high energy technology is integrated into a hybrid battery system, where it is supported by a highest power lithium-titanate technology. Three hybrid battery system configurations are systematically derived for a high class vehicle with different performance requirements. On the basis of an overall vehicle simulation model, comprising a thermal model of the lithium metal polymer battery pack, the performance of the system is evaluated under regular and extreme driving conditions. The results indicate that battery hybridization makes a reasonable utilization of the lithium metal polymer battery in an electric vehicle possible. The power capability of the overall battery system in discharge as well as charge direction is significantly increased. Moreover, the system allows for a wider utilization of overall battery system's energy, resulting in an increase of drivable distance. Furthermore, additional functionalities of the hybrid battery system are discussed, such as warm-up procedure, low temperature performance enhancement and redundancy.

Co3 O4 Nanosheets as Active Material for Hybrid Zn Batteries.

The rapid development of electric vehicles and modern personal electronic devices is severely hindered by the limited energy and power density of the existing power sources. Here a novel hybrid Zn battery is reported which is composed of a nanostructured transition metal oxide-based positive electrode (i.e., Co3 O4 nanosheets grown on carbon cloth) and a Zn foil negative electrode in an aqueous alkaline electrolyte. The hybrid battery configuration successfully combines the unique advantages of a Zn-Co3 O4 battery and a Zn-air battery, achieving a high voltage of 1.85 V in the Zn-Co3 O4 battery region and a high capacity of 792 mAh gZn-1 . In addition, the battery shows high stability while maintaining high energy efficiency (higher than 70%) for over 200 cycles and high rate capabilities. Furthermore, the high flexibility of the carbon cloth substrate allows the construction of a flexible battery with a gel electrolyte, demonstrating not only good rechargeability and stability, but also reasonable mechanical deformation without noticeable degradation in performance. This work also provides an inspiring example for further explorations of high-performance hybrid and flexible battery systems.

Multi-timescale power and energy assessment of lithium-ion battery and supercapacitor hybrid system using extended Kalman filter

The power capability and maximum charge and discharge energy are key indicators for energy management systems, which can help the energy storage devices work in a suitable area and prevent them from over-charging and over-discharging. In this work, a model based power and energy assessment approach is proposed for the lithium-ion battery and supercapacitor hybrid system. The model framework of the lithium-ion battery and supercapacitor hybrid system is developed based on the equivalent circuit model, and the model parameters are identified by regression method. Explicit analyses of the power capability and maximum charge and discharge energy prediction with multiple constraints are elaborated. Subsequently, the extended Kalman filter is employed for on-board power capability and maximum charge and discharge energy prediction to overcome estimation error caused by system disturbance and sensor noise. The charge and discharge power capability, and the maximum charge and discharge energy are quantitatively assessed under both the dynamic stress test and the urban dynamometer driving schedule. The maximum charge and discharge energy prediction of the lithium-ion battery and supercapacitor hybrid system with different time scales are explored and discussed.

Hybrid Lithium Iron Phosphate Battery and Lithium Titanate Battery Systems for Electric Buses

Electric buses face problems of short driving range, slow charging, and high cost. To improve the performance of electric buses, a novel hybrid battery system (HBS) configuration consisting of lithium iron phosphate (LFP) batteries and Li-ion batteries with a Li4Ti5O12 (LTO) material anode is proposed. The configuration and control of the HBS are first studied, and a LFP battery degradation model is built. Simulation result indicates that the HBS can help us to mitigate LFP battery degradation. Then, the HBS is optimally sized for electric buses to achieve minimum cost. The daily bus operation and charging patterns as well as LFP battery degradation are considered. The optimal HBS has 10.7% and 19.3% lower total cost than the single LTO-battery and LFP-battery configurations, and has higher range flexibility than the single LTO-battery configuration.

Hybrid thermoelectric battery electrode FeS2 study

There has been a recent push to develop powerful and safe batteries with enhanced application needs and safety requirements. A new thermoelectric hybrid battery (TEHB) system has been proposed to utilize the battery waste heat, FeS2 as an example, to further reproduce electricity and decrease temperatures as the battery is discharging and charging. Therefore, the thermoelectric properties of FeS2 as battery electrode are studied in order to enhance its thermoelectric performance and develop a system to utilize battery heat efficiently and securely. Here, FeS2 thermoelectric material is firstly prepared with hydrothermal method, followed by second-phase Fe7S8 with higher electrical conductivity which was introduced through newly designed annealing process. The results showed that the electrical conductivity of FeS2 that was annealed at 873K reached 136Scm−1 at 300K and 302Scm−1 at 648K. These were two orders of magnitude higher than the other synthesized samples. When Fe7S8 nano-crystals were introduced, there was a decrease in lattice thermal conductivity and an increase in Seebeck coefficient. These results are an important step in improving the battery efficiency by converting the unavoidable heat that was generated by battery into electricity.

The Great Chemistry Race

The Great Chemistry Race

A lithium ion/oxygen hybrid battery with high energy and high power.

A novel lithium ion/oxygen hybrid battery system is proposed that uses the advantages and minimizes the disadvantages of both lithium-ion batteries (LIBs) and lithium-oxygen batteries (LOBs). In it, the LOB-part plays range-extending and high-power output roles, while using the discharge-priority of the LIB-part is suggested to compensate the cycling-life shortcomings of the LOB-part.

Adaptive Fuzzy Logic Control of Fuel-Cell-Battery Hybrid Systems for Electric Vehicles

In this paper, we propose an adaptive control approach with fuzzy logic parameter tuning (AFLPT) for the energy management of electric vehicles that are using fuel cell battery hybrid systems. The controller is adaptive to different driving conditions including normal, regenerative, and overload conditions. Specifically, the power flow between the fuel cell (FC) and the Li-ion battery is controlled in real time to maintain the battery state of charge (SOC) at a desirable level while satisfying the FC dynamic constraints. For guaranteeing performance in different driving conditions, the FLPT is integrated with the adaptive controller. Moreover, theoretical properties of the designed controller are analyzed. Simulation and experiment results illustrate the effectiveness of the proposed strategy for FC-battery hybrid systems in electric vehicles.